This invention relates generally to a system for maintaining the temperature of components in an electronic system within a predetermined range. More particularly, the invention pertains to a refrigeration system having multiple evaporators connected in series to cool multiple heat generating components in an electronic system and a supplemental heating system having multiple individual heaters to reduce temperature variation among the components in a multi-component system.
The components (e.g., processors, micro-controllers, high speed video cards, disk drives, semi-conductor devices, etc.) of an electronic system are generally known to generate rather significant amounts of heat. It has been found that the performance and reliability of the heat generating components typically deteriorate as the components become increasingly heated and may cause component failure. Electronic systems are thus generally equipped with a mechanism (e.g., a fan) attached to the housing of the electronic system to cool the components as well as the interior of the electronic system. Although these types of mechanisms have been relatively effective in cooling the components of certain types of electronic systems, they have been found to be relatively insufficient to cool the faster and more powerful components of today""s electronics.
With the advent of more powerful components which generate greater amounts of heat, the possibility that the components will overheat has drastically increased. One solution to the overheating problem has been to directly cool the components themselves. In this regard, refrigeration systems have been implemented to directly cool the components. In these types of systems, an evaporator is positioned in thermal contact with a surface of the component to be cooled. These types of systems have been relatively effective in maintaining the temperatures of individual computer components within acceptable ranges. However, when an electronic system possesses a number of components (xe2x80x9cmulti-component systemxe2x80x9d), known refrigeration systems suffer from a variety of drawbacks and disadvantages.
For instance, one known technique of reducing the temperature of components in a multi-component system is to rely upon a single refrigeration system possessing a plurality of evaporators aligned in series along each of the components. One disadvantage associated with known serially positioned evaporators is that they generally do not compensate for varying heat loads in the components to substantially reduce the temperature variation among the components. That is, these types of systems do not compensate for the possibility that evaporators positioned downstream from other evaporators may be adversely affected (e.g., downstream evaporators may receive superheated fluid which may actually cause a rise in their temperature). In addition, they do not compensate for the possibility of evaporators positioned relatively upstream and producing a relatively low heat load, may actually be cooled below recommended operating temperatures.
According to one aspect, the present invention provides for the independent control of individual component temperatures by utilizing supplemental heaters in conjunction with metering the mass flow rate of refrigerant to a series of evaporators in a multi-load refrigeration system based on the heat load of the system without suffering from the drawbacks and disadvantages associated with known refrigeration systems.
According to a preferred embodiment, the present invention relates to a thermal regulating system for maintaining individual temperatures of a plurality of components within a predetermined temperature range. The thermal regulating system includes a refrigeration system having a refrigerant contained in a refrigerant line and a valve capable of being electronically controlled. The valve is configured to control superheat formation in the refrigeration system. The thermal regulating system further includes a plurality of evaporators configured for thermal attachment to the components and a supplemental heating system. In this regard, the refrigeration system and the supplemental heating system are operable to maintain each of the plurality of components within the predetermined temperature range.
Additionally, the present invention pertains to a method for thermally regulating multiple components of a computer system having multiple fluctuating heat loads. In the method, a flow of a refrigerant is controlled through a refrigerant line in a refrigeration system having a variable capacity compressor and a plurality of evaporators and a valve. The valve is configured to meter the flow of the refrigerant through the plurality of evaporators which are configured for thermal attachment to the multiple components. A temperature of the refrigerant is sensed in a position generally downstream of the plurality of evaporators, the sensed temperature is relayed to a controller, and a signal from the controller is sent to the valve to modify the flow of the refrigerant through the plurality of evaporators in response to the temperature being outside a predetermined superheat temperature range.
In accordance with another aspect, the present invention relates to a multi-load thermal regulating system for maintaining individual temperatures of a plurality of heat generating components within a predetermined temperature range. The thermal regulating system includes a plurality of evaporators thermally attachable to a respective heat generating component. The plurality of evaporators are connected in a serial arrangement. The thermal regulating system further includes a plurality of supplemental heaters. Each of the supplemental heaters are operable to supply supplemental heat to a respective component of the heat generating components.
The thermal regulating system further includes a refrigerant line for conducting refrigerant through the plurality of evaporators and a variable speed compressor connected to the refrigerant line. The variable speed compressor is operable to control the mass flow rate of the refrigerant through the refrigerant line. The thermal regulating system further includes a valve connected to the refrigerant line and configured to be manipulated by a controller in response to the sensed superheat of the refrigerant. Thus, the valve is operable to control the superheat of the refrigerant between the valve and the superheat sensor. Additionally, the controller is configured to transmit signals to the variable speed compressor to vary the mass flow rate of the refrigerant in response to a plurality of sensed temperature measurements measured by a plurality of component temperature sensors.